KR101398344B1 - Method for screening used secondary battery, rebuilt battery pack, vehicle and battery operated device incorporating same, and method for manufacturing rebuilt battery pack - Google Patents

Abstract

A rechargeable battery pack using a secondary rechargeable battery having characteristics matched by the sorting method selected by a proper secondary rechargeable battery, a vehicle using the rechargeable battery, and a rechargeable battery using the rechargeable battery, Thereby manufacturing a matched rebuilt battery pack. The method for selecting a secondary battery according to the present invention is characterized in that the characteristic of the battery resistance BRD with respect to the use period is measured for the battery 1 having the bist stub shape by the resistance measurement step S2 And a period threshold value Rp for identifying whether the battery 1 is in the initial resistance high period A or the final resistance high period C and the middle resistance low period B, (S4) for discriminating whether or not the battery resistance (BRD) of the battery is large or small.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a rechargeable battery pack, a rechargeable battery pack, a rechargeable battery pack, a rechargeable battery pack, a rechargeable battery pack, METHOD FOR MANUFACTURING REBUILT BATTERY PACK}

The present invention relates to a method of selecting a used secondary battery, a rebuilt battery pack using the used secondary battery selected by the selection method, a vehicle using the same, and a battery using device. The present invention also relates to a method of manufacturing a rebuilt battery pack using a used secondary battery.

Recently, hybrid cars and electric vehicles have been put to practical use by research and development. As such secondary batteries for automobiles, secondary batteries of high capacity and high output such as nickel-hydrogen secondary batteries and lithium ion secondary batteries (hereinafter simply referred to as batteries) are used.

However, when the use of such a secondary battery becomes full-scale, a large number of used secondary batteries are generated due to the discarding of the vehicle or the exchange of the battery (battery). Incidentally, the used secondary battery includes a failure, a defective characteristic, or a battery having reached the end of its life, but it is expected that many secondary batteries are still available. Therefore, it is required to appropriately reuse the used secondary battery from the viewpoints of environmental demands and the resources involved in manufacturing the battery, and from the viewpoint of effective use of energy. It is also conceivable that, in the assembled battery, a used secondary battery is used instead of a new battery in order to remove a specific battery that has failed or severely deteriorated and replace the other battery.

However, even if the battery is still usable, it is predicted that each used secondary battery will pass through various histories until it is assembled as a used product. Although there are variations in the characteristics of the battery, there is a variation in the production, but the use history after that (for example, the number of years of use and the usage pattern (whether or not charging and discharging are performed by flowing a large current in most cases, thermal environment such as cold or surge) ], The characteristics and degree of deterioration are greatly different.

On the other hand, in automobiles and the like, there is little use of the battery alone, and a plurality of (for example, twelve) used secondary batteries are collected to reconstruct (rebuild) a battery pack (small battery pack) In many cases, a battery pack (large battery pack) is reconfigured (rebuilt) by using a plurality of battery packs and mounted on a vehicle in many cases.

However, when the used secondary batteries of the same part number (model number) are assembled into a battery pack, when the characteristics of secondary batteries used or the degree of deterioration thereof are different from each other, The behavior of the battery is different from each other, so that proper charging and discharging can not be carried out or, in some cases, the battery may be diagnosed as a failure. Alternatively, although a battery pack is formed (rebuilt), some of the batteries become early in life, and the rebuilt battery pack itself may become unusable early.

SUMMARY OF THE INVENTION The present invention has been made in view of such problems, and it is an object of the present invention to provide a method of selecting a suitable secondary battery. Another object of the present invention is to provide a rebuilt battery pack using a used secondary battery whose characteristics selected by this sorting method are matched. The present invention also provides a vehicle and a battery-powered device using the same. It is another object of the present invention to provide a manufacturing method for manufacturing a rebuilt battery pack in which characteristics of each battery are matched while using a used secondary battery.

(1) One mode of the present invention for solving the above problems is characterized in that the battery resistance is gradually lowered in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears, And a secondary battery having a characteristic in which a battery resistance gradually increases at an early stage of the usable period and a relatively high resistance period of the battery resistance is exhibited, A method of selecting a used secondary battery, the method comprising: a resistance measuring step of measuring a battery resistance of the used secondary battery; and a resistance measuring step of measuring a resistance of the used secondary battery in the initial resistance high period or the high resistance period, , It is determined whether or not the battery resistance of the used secondary battery is larger or smaller than the period threshold value The screening method of the used secondary battery comprising a step of determining resistance.

However, in batteries such as high-capacity high-output Ni-MH secondary batteries and lithium ion secondary batteries for automobiles and the like, the battery resistance (resistance of the battery by the DC-IR method or the AC-IR method) Upon observation, we were able to draw a rough bathtub curve.

That is, at the initial stage, the battery resistance is relatively high, and the battery resistance decreases with the lapse of use time. This period of time, for example, depends on the use (driving) situation in a secondary battery for automobiles, but continues for several months to two years.

In the subsequent middle stage, the battery resistance is relatively low, and does not change even after the use time has elapsed, and becomes almost constant. This period lasts for, for example, 5 to 10 years in a secondary battery for automobiles.

In the subsequent boiling stage, the battery resistance increases with the use time, and the battery resistance becomes relatively high. This period of time, for example, in a secondary battery for automobiles, lasts for a year or two. Thereafter, when the battery resistance exceeds the allowable maximum resistance value, the life of the battery is terminated.

On the other hand, in the above-described sorting method, with respect to the used secondary battery having the above-described characteristics, in the resistance discriminating step, by using the battery resistance of the used secondary battery, the used secondary battery to be judged has a high battery resistance (Hereinafter, also referred to as period B) in which the battery resistance is low (hereinafter, also referred to as period B) in which the battery resistance is low (hereinafter also referred to as period B) . As a result, it is possible to easily and appropriately select whether the secondary battery is in the initial high-resistance period or the high-resistance period and in the low-middle-resistance period.

The battery resistance of the secondary battery used for sorting includes DC resistance of the battery measured by the DC-IR method and AC resistance of the battery measured by the AC-IR method.

The term threshold to be set is, for example, a value which is lower than the minimum value of the battery resistance at which the battery can be used, and is set to a value equal to or higher than the maximum value of the battery resistance at which the battery can be taken during the low-middle resistance value period.

(2) In addition, for the used secondary battery having the battery resistance larger than the period threshold value, the method for sorting the used secondary battery described above, based on the use history information of the used secondary battery, And a period discriminating step of discriminating whether the battery belongs to the initial resistance high period or the high resistance period.

In the secondary cell sorting method, the used secondary battery in which the battery resistance is larger than the period threshold value, that is, the secondary battery in the initial resistance high period (A period) or the remainder resistance high period (C period) , It is determined based on the use history information of the used secondary battery whether the used secondary battery belongs to the initial resistance high period (period A) or the secondary resistance period (period C).

As a result, for the secondary battery having the above-described characteristics, it is possible to appropriately identify which period (stage) of the three secondary batteries the secondary battery is in, and to appropriately perform processing such as reuse or disposal have.

Further, even in the case of reconstructing the battery pack by collecting a plurality of used secondary batteries, it is possible to construct the battery pack by collecting the same used secondary battery in the step (period), and thus, It is possible to prevent problems such as overvoltage and overcharging, and to form a battery pack with stable characteristics.

The usage history information may include the date of manufacture of the battery, the date of use of the battery, the period of use of the battery, and the operating time of the battery (actual use time).

In addition, as the use history information of the used secondary battery, when the used secondary battery is for automobiles, the traveling distance of the automobile during the period in which the battery is used may be used.

(3) The method for sorting used secondary batteries as described above, further comprising the step of dividing the used secondary battery having the battery resistance smaller than the period threshold value into a plurality of layers according to the size of the battery resistance The secondary battery can be selected as the secondary battery.

Even in the case of a used secondary battery belonging to the same middle-stage low-resistance period (period B), there is a variation in the value of the battery resistance.

On the other hand, when the used secondary battery belongs to the middle-stage low-resistance period (period B) in the case of the secondary battery having the battery resistance lower than the period threshold value in the sorting method of this battery, It is classified according to the size of the battery resistance. As a result, it is possible to finely layer the used secondary batteries belonging to the low-middle-resistance-period, thereby collecting the used secondary batteries with similar characteristics.

(4) The secondary battery according to claim 1, wherein the secondary battery has a DC resistance that increases as the temperature of the battery decreases, within a usable temperature range, and at a relatively high temperature range, Temperature range, a change in DC resistance due to temperature is large in a low temperature region of relatively low temperature, a DC resistance of three times or more of a DC resistance in a high temperature region, Wherein the secondary battery has a characteristic in which the DC resistance increases more rapidly as the temperature of the battery decreases in the temperature region and the battery resistance is smaller than the period threshold or the secondary battery, Of the permissible voltage range from the allowable minimum voltage to the allowable maximum voltage under the environment of Based on the length of the discharge time from the discharge start voltage of the discharge cell to the predetermined discharge end voltage within the lower one fifth of the allowable voltage range, And a step for each layer of the discharge time.

In this cell sorting method, when the secondary battery used in the B period or in the steps of the resistance layer is discharged in a constant power discharge or a constant current discharge under an environment of an intermediate temperature region where the DC resistance of the battery is slightly higher than the high temperature region, Based on the length of the discharge time up to the termination voltage, is again divided into a plurality of layers.

Therefore, by measuring the battery resistance (DC-IR method, AC-IR method), it is possible to appropriately detect the difference in battery characteristics under an environment of an intermediate temperature region of a relatively low temperature, which is unknown. As a result, the used secondary battery can be layered more finely, and the used secondary batteries can be collected from each other.

Particularly, batteries having comparatively low temperatures and having characteristics similar to those in an intermediate temperature region where the DC resistance of the battery is slightly increased can be collected individually for each layer. This makes it possible to easily form a battery pack having stable characteristics and a combined battery (large battery pack) in which the difference in characteristics between batteries is less likely to occur in practical use of the battery under an environment of a relatively low temperature and an intermediate temperature range .

In a nickel-metal hydride secondary battery or a Li ion secondary battery having a temperature range of about -30 캜 to 60 캜, the intermediate temperature range is about -20 캜 to 10 캜. In this case, the low temperature region corresponds to a range of -30 占 폚 to -20 占 폚, and the high temperature region corresponds to a range of 10 占 폚 to 60 占 폚. Further, in the low temperature region, the DC resistance is three times or more as compared with the high temperature region.

As the discharge start voltage, a suitable voltage value within a high voltage range of the upper fifth of the five ranges in which the allowable voltage range from the allowable minimum voltage to the allowable maximum voltage is divided into five is selected. This is because discharging is started from a value close to the allowable maximum voltage (voltage of full charge (SOC: 100%)), so that the characteristic of the battery with a relatively large charged amount can be reflected in the discharging time. Therefore, as the discharge starting voltage, it is preferable to set the voltage value to the allowable maximum voltage (full charge (SOC: 100%)).

As the discharge end voltage, a suitable voltage value within the lower 1/5 lower voltage range which is the lowest range among the five ranges in which the allowable voltage range from the allowable minimum voltage to the allowable maximum voltage is divided into five is selected. This is because discharging time can be reflected in the battery characteristic in a state in which the relatively small amount of charge is low by discharging to a value close to the allowable minimum voltage (voltage of the full discharge (SOC: 0%)]. Therefore, as the discharge end voltage, it is preferable to set the voltage value to the allowable maximum voltage (full discharge (SOC: 0%)).

The magnitude of the current flowing during the constant power discharge or the constant current discharge can be set within a range of a current flowing when the battery is actually used, for example, when the battery is mounted on a vehicle, It is recommended that the maximum current is not exceeded. It is also preferable to set it to 10 C or less. If a large current is caused to flow, the discharging is terminated in a short period of time, so that the measurement accuracy of the discharging time is lowered and it is difficult to make a proper comparison. This is because the influence of the voltage drop due to the electrolyte resistance generated for discharging a large current is large and it is difficult to grasp the change in the discharge time caused by the deterioration of the characteristics of the battery electrode.

Therefore, in the secondary battery selecting method according to any one of the above-mentioned aspects, the secondary battery having the battery resistance smaller than the period threshold is charged at a current of 10 C or less from the fully charged state under an environment of 10 캜 to -20 캜 It is preferable that the secondary battery selection method is provided with the step of the discharge time layer layer which is divided into a plurality of layers on the basis of the length of the discharge time until reaching the allowable minimum voltage when the constant electric power discharge or the constant current discharge is performed Do.

Further, in this sorting method, the range of the voltage to be changed by the discharge is wide. As a result, the difference in the discharge time due to the difference in the battery characteristics becomes large, and each battery can be layered more appropriately.

(5) Further, the battery resistance is gradually lowered in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears, and the middle resistance low period in which the battery resistance is relatively low in the middle stage of the usable period A rechargeable battery having a characteristic in which the battery resistance gradually increases at the end of the usable period and the battery resistance is relatively high and the rechargeable battery has a high period, The secondary battery may be a rebuilt battery pack that is in the middle-period low resistance period by the secondary battery selection method described in the above-mentioned configuration (1).

In this rewritable battery pack, a battery that has been in the middle low resistance period (period B) by sorting is used. This makes it possible to prevent problems such as overvoltage and overcharging of some of the batteries due to the characteristic deviation between the batteries because the variation in characteristics between the batteries used in the battery pack is small. In addition, since the battery of period B is used, it is possible to obtain a rebuilt battery pack having stable characteristics with less variation in characteristics of each battery.

Further, since the battery in the C period is not mixed, it is also possible to prevent a problem that a part of the battery in the rebuilt battery pack reaches the end of its life early and the rebuilt battery pack becomes unusable in the early stage.

In addition, the rebilt battery pack includes a plurality of batteries in addition to a battery pack, and a plurality of such battery packs are combined to form a battery pack (large packed battery).

(6) Further, the battery resistance is gradually lowered in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears, and the medium resistance low period in which the battery resistance is relatively low in the middle stage of the usable period A rechargeable battery having a characteristic in which the battery resistance gradually increases at the end of the usable period and the battery resistance is relatively high and the rechargeable battery has a high period, The secondary battery may be a rebuilt battery pack which is in the initial resistance high period by the secondary battery selection method described in the above-mentioned constitution (2).

In this rewritable battery pack, a battery which has been in the initial resistance high period (A period) by sorting is used. As a result, the battery pack used in the battery pack has a small variation in characteristics and can be used as a rebuilt battery pack in which problems such as overvoltage and overcharging of some batteries due to characteristic deviations between batteries are prevented.

Further, since the battery in the C period is not mixed, it is also possible to prevent a problem that a part of the battery in the rebuilt battery pack reaches the end of its life early and the rebuilt battery pack becomes unusable in the early stage.

In addition, since the rechargeable battery pack of the remaining A life period is collected, the rechargeable battery pack can be used over a long period of time.

(7) Further, the battery resistance is gradually lowered in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears, and the medium resistance low period in which the battery resistance is relatively low in the middle stage of the usable period A rechargeable battery having a characteristic in which the battery resistance gradually increases at the end of the usable period and the battery resistance is relatively high and the rechargeable battery has a high period, The secondary battery according to any one of claims 1 to 3, wherein the secondary battery is a secondary battery selected from the group consisting of a plurality of secondary batteries, It is good to use a rebilt battery pack that belongs to.

In this rewritable battery pack, with respect to a cell which has been selected in the middle stage resistance low period (period B), it is divided into a plurality of layers by the cell resistance, and a cell belonging to one layer or a part of adjacent layers I am using it. This makes it possible to prevent the problems such as overvoltage and overcharging of some of the batteries due to the characteristic deviation between the batteries because the variation in characteristics between the batteries used in the battery pack is further reduced. In addition, since the battery of the period B is used, it is possible to obtain a rebuilt battery pack having stable characteristics with less change in characteristics of each battery.

Further, since the battery in the C period is not mixed, it is also possible to prevent a problem that a part of the battery in the rebuilt battery pack reaches the end of its life early and the rebuilt battery pack becomes unusable in the early stage.

(8) Alternatively, the battery resistance is gradually lowered in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears, and the middle resistance period in which the battery resistance is relatively low in the middle stage of the usable period A rechargeable battery having a characteristic in which the battery resistance gradually increases at the end of the usable period and the battery resistance is relatively high and the rechargeable battery has a high period, And the secondary battery is a battery pack. In the secondary battery selecting method described in the above-mentioned constitution (4), the secondary battery is characterized in that one of the plurality of layers layered by the discharging time layer- Of the battery pack of the present invention.

In this rewritable battery pack, a battery which has been selected in the middle period of low resistance period (period B), or a battery which is layered by battery resistance, is divided into plural layers by the discharge time again, Or a cell belonging to a certain adjacent layer is used. As a result, the characteristics of batteries which can not be detected by the battery resistance (DC-IR method, AC-IR method) between the batteries used in the battery pack are also matched with each other, It is possible to prevent problems such as overvoltage and overcharging. In particular, it is possible to provide a rebil battery pack having characteristics that are difficult to exhibit a characteristic difference in an intermediate temperature region of relatively low temperature. In addition, since the battery of the period B is used, it is possible to obtain a rebuilt battery pack having stable characteristics with less change in characteristics of each battery.

Further, since the battery in the C period is not mixed, it is also possible to prevent a problem that a part of the battery in the rebuilt battery pack reaches the end of its life early and the rebuilt battery pack becomes unusable in the early stage.

(9) Alternatively, another mode for solving the above problem is characterized in that the battery resistance is gradually lowered in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears, The middle resistance low period in which the battery resistance is relatively low appears and the battery resistance slowly rises at the end stage of the usable period and at the same time the secondary resistance high period in which the battery resistance is relatively high appears, Wherein the secondary battery is a rebuilt battery pack in which the secondary battery is assembled and reconfigured.

In this rewritable battery pack, secondary secondary batteries belonging to the low middle resistance period (period B) are collected. This makes it possible to prevent problems such as overvoltage and overcharging of some of the batteries due to the characteristic deviation between the batteries because the variation in characteristics between the batteries used in the battery pack is small. In addition, since the battery of the period B is used, it is possible to obtain a rebuilt battery pack having stable characteristics with less change in characteristics of each battery.

On the other hand, since the cells in the period C are not mixed, the problem that the lifetime of some of the batteries in the rebuilt battery pack reaches its early life and the rebuilt battery pack becomes unusable early can be prevented.

(10) Further, another form for solving the above-mentioned problem is a vehicle in which any one of the above-described rebuilt battery packs is mounted, and electric energy from the rebuilt battery pack is used for all or a part of the power source.

Since this vehicle is equipped with the above-mentioned rebuilt battery pack, the vehicle can be made inexpensive as compared with the case where a new battery is used, and at the same time, the used battery can be effectively used.

Examples of the vehicle include an electric car, a plug-in hybrid car, a hybrid car, a hybrid railway car, an electric forklift, an electric wheelchair, an electric assist bicycle, and an electric scooter.

(11) Another mode for solving the above-mentioned problem is a battery-operated device in which any one of the above-described rebuilt battery packs is mounted, and the rebuilt battery pack is used as at least one of the energy sources.

Since this battery-operated device is mounted with the above-mentioned rebuilt battery pack, it can be made inexpensive as compared with the case where a new battery is used, and at the same time, the used battery can be effectively used.

Examples of the battery-use device include a personal computer, a mobile phone, a battery-driven power tool, an uninterruptible power supply device, various battery-powered household appliances, an office appliance, and an industrial appliance.

(12) Another mode for solving the above problem is characterized in that the battery resistance is gradually lowered in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears, The middle resistance low period in which the battery resistance is relatively low appears and the battery resistance slowly rises at the end stage of the usable period and at the same time the secondary resistance high period in which the battery resistance is relatively high appears, A method of manufacturing a rebuilt battery pack in which a secondary battery is assembled and reconfigured, characterized in that the used secondary battery has a period threshold value that identifies whether the initial secondary battery is in the initial high resistance period or the expiration resistance high period, A resistance discriminating step for discriminating whether the battery resistance of the used secondary battery is large or small, A method of manufacturing the battery pack re-built to the period threshold value than that of the cell resistance is small collection of the used secondary batteries, having a first type of reconstruction step of reconstructing the battery pack.

In the method of manufacturing the rebuilt battery pack, the used secondary batteries belonging to the middle-period low resistance period (period B) are collected and the rebuilt battery pack is reconfigured in the first type re-forming step.

This makes it possible to reduce the variation in characteristics between the batteries used in the rebuilt battery pack and to prevent the problem of overvoltage and overcharging of some batteries due to the characteristic deviation between the batteries, Can be manufactured.

In addition, since the cells of period B are used, variations in the characteristics of each cell are reduced, and a rebilted battery pack having stable characteristics can be manufactured. This makes it possible to manufacture a rebilted battery pack having characteristics similar to each other and having a stable characteristic with less change in battery resistance.

Further, since the battery in the C period is not mixed, it is also possible to prevent a problem that a part of the battery in the rebuilt battery pack reaches the end of its life early and the rebuilt battery pack becomes unusable in the early stage.

(13) The method for manufacturing a rebuilt battery pack as described above, wherein, in the used secondary battery having the battery resistance smaller than the period threshold value, the used secondary battery is divided into a plurality of layers And a second step of reusing the secondary batteries belonging to one layer or a part of adjacent layers among the plurality of layers separated by the battery resistance to reconstruct the battery pack And a second type of re-forming step.

In this method of manufacturing a rebuilt battery pack, a used secondary battery having a battery resistance lower than the period threshold value, that is, a used secondary battery belonging to the middle term low resistance period (period B) Depending on their size, they are layered in multiple layers. Then, the batteries belonging to one layer or a part of the adjacent layers are collected together to produce a rebuilt battery pack. This makes it possible to prevent a problem of overvoltage and overcharging of some of the batteries due to characteristic deviations between the batteries, which is further reduced in the characteristic deviation between the batteries used in the battery pack. In addition, since the battery of period B is used, it is possible to manufacture a rebuilt battery pack having stable characteristics with less change in characteristics of each battery even when used.

(14) The method of manufacturing a rebuilt battery pack according to any one of the above-mentioned items, wherein the secondary battery has a DC resistance that increases as the temperature of the battery decreases, within a usable temperature range, Temperature range of the high-temperature region, the change of the direct-current resistance by the temperature is small, the change of the direct-current resistance by the temperature is large in the low-temperature region of relatively low temperature, In the intermediate temperature region between the low temperature regions, there is a characteristic in which the DC resistance increases more rapidly as the temperature of the battery decreases, and the battery resistance is smaller than the period threshold value, Of the allowable voltage range from the allowable minimum voltage to the allowable maximum voltage under the environment of the intermediate temperature region, To the predetermined discharge end voltage within a lower voltage range of the lower one-fifth of the allowable voltage range, based on the length of the discharge time from the predetermined discharge start voltage within the high voltage range And a discharge time layer step of layering again a plurality of layers, wherein, in place of the first type recomposing step or the second type recomposing step, one of a plurality of layers laminated by the length of the discharge time or And a third type recomposing step of collecting used secondary batteries belonging to some adjacent layers and reconstructing the battery pack.

In the method for manufacturing the rebuilt battery pack, the used secondary battery in the period B or the used secondary battery layered in the battery resistance is further divided into a plurality of layers based on the length of the discharging time And the cells belonging to one layer or a part of the adjacent layers are collected to prepare a rebuilt battery pack. As a result, the difference in cell characteristics under an environment of an unknown intermediate temperature range is appropriately divided by the battery resistance (DC-IR method, AC-IR method), and secondary batteries of similar characteristics are collected, Pack can be manufactured. Particularly, since a battery having characteristics similar to each other under an environment of a relatively low temperature and an intermediate temperature range can be used, it is possible to stably use the rewritable battery pack in an environment of an intermediate temperature region A battery pack can be manufactured.

Particularly, in the above-described method of manufacturing a rebuilt battery pack, the secondary battery having the battery resistance smaller than the period threshold or layered in the step of each resistor layer is subjected to full charge And a step for each discharge time layer that is divided into a plurality of layers based on the length of the discharge time from the previous state to the allowable minimum voltage when a constant current discharge or a constant current discharge is performed at a current of 10 C or less, 1 type reconstruction step or the second type reconstruction step, a used secondary battery belonging to one layer or a part of adjacent layers among the plurality of layers laminated by the length of the discharge time is collected and a third Type rebuilding step, and a type re-forming step.

In this manufacturing method, the range of the voltage to be changed to the discharge is wide in the step of each discharge time layer layer. As a result, the difference in the discharge time due to the difference in the battery characteristics is largely different, and the cells can be more appropriately layered.

Further, it is also possible to employ the following sorting method without selecting the batteries by comparing the battery resistance of the used secondary battery with the period threshold value. That is, the secondary battery is already selected and used, and the secondary battery has a DC resistance which increases as the temperature of the battery decreases, within a usable temperature range, and at a relatively high temperature, Temperature range, a change in DC resistance due to temperature is large in a low temperature region of relatively low temperature and a DC resistance of three times or more of a DC resistance in a high temperature region, Wherein the secondary battery has a characteristic in which the DC resistance is accelerated as the temperature of the battery is lowered, and the secondary battery is used in an upper half of the allowable voltage range from the allowable minimum voltage to the allowable maximum voltage under the environment of the intermediate temperature region, And a constant-current discharge or a constant-current discharge is performed from a predetermined discharge initiation voltage within a high-voltage range of 5, There is provided a method for selecting a secondary battery comprising a step of repeating discharge time layers for a plurality of layers based on a length of a discharge time until reaching a predetermined discharge end voltage within a lower voltage range of the lower one- .

In the secondary cell sorting method, the used secondary cell is divided into a plurality of layers based on the length of the discharge time when static electricity discharge or constant current discharge is performed under an environment of an intermediate temperature region. Therefore, it is possible to appropriately detect a difference in cell characteristics under an environment of an intermediate temperature region of a relatively low temperature, which can not be detected by the battery resistance (DC-IR method, AC-IR method) at normal temperature, can do. Thus, it is possible to accurately collect used secondary batteries having similar characteristics. Particularly, in the use of the battery in an intermediate temperature region where the direct current resistance of the battery is slightly increased at a relatively low temperature, it is possible to select those having similar characteristics. Therefore, in practical use of the battery under the environment of the intermediate temperature region, (Small battery pack) having a stable characteristic and a battery pack such as a combined battery (large battery pack) combined with the battery pack can be easily configured.

Particularly, it is a method of selecting a used secondary battery, which is a method of selecting a used secondary battery in which the secondary battery is charged at a permissible minimum value when a constant current discharge or a constant current discharge is carried out at a current of 10 C or less from a full charge state under an environment of 10 ° C. to -20 ° C. And a discharge time layer step for depositing a plurality of layers on the basis of the length of the discharge time until reaching the voltage.

In the secondary cell sorting method, the secondary battery is selected based on the length of the discharge time from the full charge state to the allowable minimum voltage when the constant electric discharge or the constant current discharge is performed under a relatively low temperature environment Layered into a plurality of layers. This makes it possible to appropriately detect the difference in cell characteristics under a relatively low-temperature environment in which an unknown battery resistance (DC-IR method, AC-IR method) is used at room temperature, thereby allowing each battery to be layered. Thus, it is possible to accurately collect used secondary batteries of similar characteristics. Particularly, in the use of the battery in a relatively low-temperature environment, it is possible to select those having similar characteristics, so that it is difficult to show a difference in characteristics in actual use of the battery in such an environment, Battery pack) can be easily configured.

In addition, this selection method has a wide range of voltage to be changed by discharging. As a result, the difference in the discharge time due to the difference in the battery characteristics is largely different, and the cells can be more appropriately layered.

The rechargeable battery pack includes a rechargeable battery pack in which a plurality of reused secondary batteries are assembled and reconfigured. In the rechargeable battery pack, the rechargeable battery pack according to claim 2, It is also preferable to provide a rebuilt battery pack that belongs to one layer or a part of adjacent layers among the plurality of layers layered by the step.

This rewritable battery pack uses a used secondary battery whose characteristics are matched under an environment of an intermediate temperature region at a relatively low temperature by sorting. This makes it possible to match the characteristics of the battery which can not be detected by the battery resistance (DC-IR method, AC-IR method) between the batteries used in the battery pack. As a result, It is possible to prevent problems such as overvoltage and overcharging. Particularly, in the intermediate temperature region of relatively low temperature, a difference in characteristics is hard to appear and the battery pack can be stably used.

The present invention also provides a method of manufacturing a rebuilt battery pack in which a plurality of used secondary batteries are assembled and reconfigured, and the secondary battery is used in such a manner that the DC resistance of the battery decreases as the temperature of the battery decreases The change of the direct current resistance due to the temperature is small in the high temperature region of relatively high temperature and the change of the direct current resistance by the temperature is large in the low temperature region of relatively low temperature and the direct current resistance of three times or more of the direct current resistance in the high temperature region And the DC resistance is accelerated as the temperature of the battery is lowered in an intermediate temperature region between the high temperature region and the low temperature region and the secondary battery is allowed to be allowed from the allowable minimum voltage under the environment of the intermediate temperature region A predetermined discharge start voltage within a high voltage range of 1/5 of the upper half of the allowable voltage range up to the maximum voltage Based on the length of the discharge time until reaching the predetermined discharge end voltage within the lower one-fifth of the allowable voltage range by a constant electric power discharge or a constant current discharge, And a fourth type reconstruction step of assembling the used secondary batteries belonging to one layer or a part of adjacent layers among the plurality of layers separated by the discharge time and reconstructing the battery pack .

In this method for manufacturing a rebuilt battery pack, the used secondary battery is divided into a plurality of layers based on the length of the discharge time by the discharge time layer steps, and a battery To produce a rebilt battery pack. As a result, it is possible to appropriately layer the difference in battery characteristics under an environment of an unknown intermediate temperature range by means of the battery resistance (DC-IR method, AC-IR method), and to provide a rewritable battery Pack can be manufactured. Particularly, since a battery having characteristics similar to each other in an environment of a relatively low temperature and an intermediate temperature range can be used, in a practical use of a rebuilt battery pack under an environment of an intermediate temperature range, Pack can be manufactured.

In particular, a method of manufacturing a rebuilt battery pack in which a plurality of used secondary batteries are assembled and reconfigured, wherein the used secondary battery is charged at a current of 10 C or less from a fully charged state under an environment of 10 캜 to -20 캜 A low-temperature discharge time layer-by-layer step of depositing a plurality of layers on the basis of a length of a discharge time from a discharge to an allowable minimum voltage when an electrostatic discharge or a constant current discharge is performed; And a fourth type recomposing step of collecting the secondary batteries and reconfiguring the battery pack.

In the secondary cell sorting method, the secondary battery is selected based on the length of the discharge time from the full charge state to the allowable minimum voltage when the constant electric discharge or the constant current discharge is performed under a relatively low temperature environment Layered into a plurality of layers. This makes it possible to appropriately detect the difference in cell characteristics under a relatively low-temperature environment in which an unknown battery resistance (DC-IR method, AC-IR method) is used at room temperature, thereby allowing each battery to be layered. Thus, it is possible to accurately collect used secondary batteries of similar characteristics. Particularly, in the use of a battery in a relatively low-temperature environment, it is possible to select a battery having similar characteristics, so that it is difficult to show a difference in characteristics in actual use of the battery in such an environment, A large battery pack) can be easily configured.

In addition, this selection method has a wide range of voltage to be changed into discharge. As a result, the difference in the discharge time due to the difference in the battery characteristics is largely different, and the cells can be more appropriately layered.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view showing a flow of a used secondary battery obtained from a pre-assembled battery assembly to a time when a rebuilt pre-assembled battery is mounted on a vehicle.
2 is a graph showing a change in battery resistance (DC-IR method) with respect to the elapsed time of use.
Fig. 3 is a flow chart showing a process of sorting the cells according to the first embodiment and manufacturing the battery assemblies and assembled batteries.
4 is an explanatory diagram showing a vehicle equipped with a rebuilding battery.
Fig. 5 is a flowchart showing a process of sorting the cells according to the second embodiment, and a production flow of a battery assembly and a battery module.
Fig. 6 is a flowchart showing a process of sorting the cells according to the third embodiment, and a production flow of a battery assembly and a battery module.
7 is a graph showing the relationship between the battery temperature and the DC resistance of the battery.
8 is a graph showing a change in the battery voltage when the battery is subjected to a constant power discharge from the full charged state to the allowable minimum voltage, by measuring the battery temperature while changing the battery temperature.
Fig. 9 is a flowchart showing a process of sorting the cells according to the fourth embodiment, and a production flow of a battery assembly and a battery module.
10 is an explanatory view showing an impact driver equipped with a rebilt battery assembly.

(First Embodiment)

A first embodiment of the present invention will be described with reference to Figs. 1 to 4. Fig. The vehicle-mounted secondary battery is mounted on the vehicle 41 as a battery (secondary battery) UAB as shown in (f) in Fig. In the case where such a vehicle 41 becomes a scrap vehicle or a part of the used high-voltage battery UBP constituting the used secondary battery UAB is replaced when the used secondary battery UAB is replaced with a new one, (UAB) or a pre-assembled battery (UBP).

This used secondary cell (UAB) is composed of a plurality of secondary cell assemblies (UBP). Also, as shown in the column (a) of FIG. 1, the used battery assembly (UBP) is composed of a plurality of used secondary batteries 1 (six in FIG. 1). This used secondary cell (UAB) or secondary cell aggregate (UBP) may be recycled as it is, but a portion of the cell 1 constituting the secondary cell aggregate (UBP) is deteriorated and is not suitable for reuse . Therefore, as shown in the column (b), the used cell aggregate (UBP) is disrupted and divided into individual cells 1, so that the reusable cells 11 and the reusable cells 11, (10). In this embodiment, as will be described later, among the reusable batteries 11, a battery 12 (a battery of a period B to be described later) having a medium degree of use life and a battery (Cells in period A and period C) 13 (sorted) (see column (c)).

As shown in the column (d), the cells 12 belonging to the period B, which is one layer of the cells 11 divided into two layers of the cells 12 and 13, 21). Further, as shown in the column (e), the rebuilt battery assembly 21 is assembled to rebuild the rebuilt hybrid battery 31, and the rebuilt battery assembly 31 is mounted on the vehicle 41.

First, the battery 1 according to the first embodiment will be described. The battery 1 is a known Ni-MH secondary battery (Ni-MH secondary battery) in which a power generating element 1A of a layered type is housed in the metal shell 1B. The power generation element 1A includes a positive electrode plate, a negative electrode plate, and a separator interposed therebetween, which are not shown, and impregnated with an electrolyte solution 1C mainly composed of potassium hydroxide.

This in-vehicle battery 1 has a property that its characteristics change with use, and shows a so-called bistable type characteristic change (resistance change) as shown in Fig. That is, when the change of the direct current resistance (battery resistance) BRD of the battery measured by the DC-IR method, which is a characteristic index of the battery with respect to the use time of the battery 1, is observed, . Specifically, the battery resistance (initial resistance value Ri) is lower than the allowable maximum resistance value Rmax described later at the start of use (use time 0), but is relatively high. By the way, when the use of the battery 1 is started, the battery resistance BRD is gradually decreased. This period varies depending on the conditions of use of the battery 1 and the like, but is about two years to two years. When the battery is used to a certain extent, the battery resistance BRD is almost constant even when the use time has elapsed, and the battery resistance BRD is a period in which no change occurs. This period lasts approximately five to ten years. Further, when the battery 1 is used after this period, the battery resistance BRD gradually rises with the use time, and eventually exceeds the allowable maximum resistance value Rmax to become the usage limit (unusable). This period lasts approximately one to two years.

In addition, there is a variation in the characteristics of each battery 1. Therefore, in FIG. 2, for example, the resistance variation DR of the battery resistance BRD at the time of use time X is indicated by a range of both arrows.

The battery resistance (DC-IR method) BRD is measured as follows.

In other words, charging / discharging is performed by changing charging / discharging of the current value I, period T seconds, discharging and idling of the current value I, and current value I in the order of I = 2C, 4C, 10C and 20C. The period T seconds is a value selected from 2 to 10 seconds, for example, T = 2 seconds. The relationship between the magnitude of each current value I at the time of charging or discharging and the battery voltage BV at that time is measured and the relationship between the voltage and the voltage is plotted for each current value with the abscissa representing the current value and the ordinate representing the voltage . Also, the regression line is drawn by the least squares method to obtain the slope of this graph (straight line). This slope corresponds to the direct current resistance (battery resistance) BRD of the battery by the law of ohm.

Then, the battery 1 is selected using the above-described characteristics. A manufacturing procedure of the screening and rebuilding battery assembly or the rebuilt base cell according to the present embodiment will be described with reference to Figs. 3 and 2. Fig.

First, in step S1 of Fig. 3, the appearance of the battery 1 is inspected, and the battery 10 having a problem (deformation such as expansion or contraction of the container, scratches, corrosion, etc.) is removed. Further, for each remaining battery 1, the battery resistance BRD is measured by the above-described method (step S2). Subsequently, in step S3, it is determined whether or not the battery 10, which has detected a short circuit, an open or other abnormal value, specifically, the battery resistance BRD is less than the allowable minimum resistance value Rmin or exceeds the allowable maximum resistance value Rmax The battery 10 is also removed.

In step S4, the measured battery resistance BRD is compared with the period threshold Rp. The period threshold value Rp is set to be lower than the minimum value of the initial resistance value Ri at which the battery 1 can be used as shown in Fig. 2 after considering the characteristic deviation of each battery 1, The battery resistance BRD considering the maximum value of the battery resistance BRD at which the battery can be taken at the time when the use time UT has elapsed and the battery resistance BRD becomes substantially constant (resistance variation DR at the use time X is considered) Of the maximum value].

2, when the battery resistance BRD reaches the threshold value Rp in the middle of the usable period UP until the life of the battery is shortened by comparison with the threshold value Rp in this period Rp) is set as the middle resistance value lower period B (B period). It is also possible to set the period in which the battery resistance BRD is higher than the threshold value Rp in the initial period of the usable period UP because the use time UT is short and the period in which the battery resistance BRD is higher than the threshold value Rp in the initial resistance value high period A do. The period in which the battery resistance BRD is higher than the threshold value Rp in the end of the usable period UP due to the long use time is set as the ending resistance value high period C (period C).

In the above-described step S4, by comparing the battery resistance BRD with the period threshold Rp, it is possible to determine whether the battery 1 is the battery 12 in the period B or the battery 13 in the other periods (periods A and C) ). That is, when the battery resistance BRD is larger than the period threshold value Rp (Yes), the process proceeds to step S11, and the battery 11 is determined to be the battery 13 in the A period or the C period.

On the other hand, if the battery resistance BRD is smaller than the period threshold value Rp, the process proceeds to step S5 to determine that the battery 11 is the battery 12 in the period B. As described above, by using the period threshold value Rp, the battery 13 in the early resistance high period (period A) or the remainder period (period C) of the secondary battery 1 [11] The battery 12 in the low resistance period (period B) can be easily and appropriately selected.

In step S6, the batteries 12 classified into the B period are collected to form (reconstitute) the rebuilt battery aggregate 21 (refer to (c) and (d) of FIG. 1). Thus, the rebilted battery assembly 21 can be manufactured.

Thus, the rebuilt battery aggregate 21 collects and reconfigures the cells 12 in the same B period. As a result, the battery resistance BRD of each battery 12 is low, so that a battery assembly having a low battery resistance can be obtained as a whole of the rebuilt battery aggregate 21.

In addition, it is possible to prevent problems such as overvoltage and overcharging of a part of the battery due to the resistance variation DR between the batteries 12 being used because the variation in characteristics between the batteries 12 being used is small. In addition, since the battery 12 of the period B is used, it is possible to make the rebounded battery assembly 21 having stable characteristics with little change in characteristics of each battery 12 even if it is used.

Conversely, since the battery 13 in the period C is not incorporated, a problem arises that the entire life of the battery in the rebuilt battery assembly 21 is short and the entire rebuilt battery assembly 21 becomes unusable early .

The rebuilt battery assembly 21 is one type (a small rebuilt battery pack) of the rebuilt battery packs.

In addition, the process proceeds to step S7 to collect (rebuild) the rebuilt battery assembly 31 using the battery 12 (refer to FIG. 1 (e)). Thus, the rebuild cell 31 can be manufactured. In addition, the re-assembled battery 31 is one type (a large rebuilt battery pack) of the rebuilt battery packs.

Even in this case, the characteristic deviation between the cells 12 used in the assembled battery 31 is small, and the performance of some cells (or the rebuilt battery assemblies 21) due to the resistance deviation DR between the cells Problems such as overvoltage and overcharging can be prevented. In addition, since the battery 12 of the period B is used, it is possible to make the battery 11 of the present invention having stable characteristics with little change in characteristics of each battery 12 even if it is used.

In step S8, the rebuilding battery 31 is incorporated in the vehicle 41 (refer to FIG. 1 (f)). Thus, it is possible to manufacture the vehicle 41 on which the rebuilt battery 31 (the rebuilt battery assembly 21) is mounted. This vehicle 41 is a hybrid vehicle that drives the engine 42, the front motor 43, and the rear motor 44 in combination as shown in Fig. The vehicle 41 includes a vehicle body 45, an engine 42, a front motor 43 attached thereto, a rear motor 44, a cable 46, and an inverter 47. The vehicle 41 is provided with a rebuilding battery 31 and uses the electric energy generated by the rebuilding battery 31 for driving the front motor 43 and the rear motor 44 .

Since the vehicle 41 is equipped with the rebuilding battery 31 (rebuilding battery pack), the vehicle 41 can be made inexpensive as compared with the case of using a new battery (assembled battery) Effective utilization can be planned.

In the first embodiment, step S2 corresponds to the resistance measurement step, step S4 corresponds to the resistance discrimination step, and steps S6 and S7 correspond to the first type reconstruction step.

(Second Embodiment)

Next, a second embodiment will be described with reference to Figs. 1, 2, and 5. Fig. In the first embodiment described above, the rebuilt battery assembly 21 and the rebuilt battery cell 31 are manufactured for the battery 12 in the period B in accordance with the steps S5 to S8, . On the other hand, in step S4, if the battery having the battery resistance BRD larger than the period threshold value Rp is selected as the battery 13 in the period A or the period C, the process proceeds to step S11, I did.

On the other hand, in the second embodiment, unlike the first embodiment, the battery 13 in the period A and period C is also replaced with the rebuilt battery assembly 121 and the rebuilt battery 131 in steps S11 to S18 And mounts the vehicle 141 on the vehicle 141 again.

Therefore, the following description focuses on the parts different from those of the first embodiment, while the description of the same parts as those of the first embodiment is omitted or simplified.

Also in the second embodiment, the battery 1 as in the first embodiment is rebuilt. That is, similar to the first embodiment, the appearance of the battery 1 is inspected at step S1, and the battery 10 having a problem is removed. Further, the battery resistance BRD is measured (step S2), and the battery 10 in which the abnormal value is detected is removed in step S3.

Subsequently, in step S4, the measured battery resistance BRD is compared with the period threshold Rp. If the battery resistance BRD is smaller than the period threshold value Rp (NO), the process proceeds to step S5, and the battery 11 is determined to be the battery 12 in the B period. Thereafter, the rebuilt battery assembly 21 and the rebuilt battery 31 are manufactured in the same manner as in steps S6 to S8 of the first embodiment, and the vehicle 41 is mounted.

On the other hand, if it is determined in step S4 that the battery resistance BRD is larger than the period threshold value Rp (YES), the process proceeds to step S11, where the battery 11 is determined to be the battery 13 in the A period or the C period.

Thereafter, in contrast to the first embodiment, the process proceeds to step S12, where it is determined from the use history information of the battery 13 whether or not the battery is in the A period. All of the batteries 1 used in the assembled battery UAB are managed for their manufacturing and use histories. Therefore, for each battery 1 (13), usage history information such as the operating time (actual use time) of the battery from the start of use exists. Therefore, the usage time (UT) of the usage history information of the battery 13 is used. Specifically, when the use time UT of the battery 13 is less than two years (YES), the process proceeds to step S13 and is referred to as the battery 14 in the A period. On the other hand, if the use time UT exceeds 2 years (NO), the process proceeds to step S17 and is referred to as the battery 15 in the C period. Thus, the battery 13 is divided into two layers (cells 14 and 15).

In step S17, the battery 15 having reached the C period proceeds to step S18 where it is discarded as a battery, decomposed, and reused as a raw material. Since the battery life (BRD) is expected to increase with use in a short period of time, rechargeable battery assemblies or assembled batteries are likely to reach the end of their life early in the early stages, making reuse difficult.

On the other hand, in step S14, the rechargeable battery assembly 121 is formed (reorganized) by collecting the batteries 14 classified into the A period (refer to FIG. 1 (d)). Thus, in the second embodiment, the rebounded battery assembly 121 can also be manufactured from the battery 14 in the period A.

In this rebounded battery assembly 121, the battery 14 that is in the period A by sorting is used. This makes it possible to prevent problems such as overvoltage and overcharging of some batteries due to a variation in resistance DR between the batteries due to a small variation in characteristics among the batteries 14 used in the battery assembly 121, (121).

In addition, since the cells 15 in the period C are not mixed, it is also possible to prevent a problem that a part of the cells in the rebuilt battery assembly 121 reaches the end of its life early and the assembled rebuilt battery becomes unusable early .

In addition, since the batteries 14 in the remaining A-life period are collected, the battery assembly of this invention can be used over a long period of time.

In step S15, the rebuilt battery assembly 121 using the battery 14 is assembled to form (rebuild) the rebuilt battery cell 131 (refer to FIG. 1 (e)). Thus, the rewritable battery 131 can be manufactured. In addition, this re-assembled battery 131 is also one of the rebuilt battery packs.

Even in this case, the characteristic deviation between the batteries 14 used in the battery module 131 is small, and the overvoltage (voltage) of some batteries (or the battery module assembly 121) due to the resistance deviation DR between the batteries And problems such as overcharging can be prevented. In addition, since the battery 14 of the period A is used, the battery cell 14 can be made to have a stable characteristic with less change in characteristics of each battery 14 even if it is used.

In step S16, the rebuilding battery 131 is built in the vehicle 141 (see Fig. 1 (f)). Thus, it is possible to manufacture the vehicle 141 on which the rebuilt battery 131 (the rebuilt battery assembly 121) is mounted. Since the vehicle 141 is the same as the vehicle 41 except for the battery 131, its description will be omitted.

Since the vehicle 141 is mounted with the rebuilt battery 131 (rebuilt battery pack), the vehicle 141 can be made inexpensive as compared with the case of using a new battery (assembled battery) Effective utilization can be planned.

In the second embodiment, step S2 corresponds to the resistance measuring step, step S4 corresponds to the resistance discriminating step, steps S6 and S7 correspond to the first type reconstruction step, and step S12 corresponds to the period discriminating step.

(Third Embodiment)

Next, a third embodiment will be described with reference to Figs. 1, 2, and 6. Fig. In the above-described first embodiment (see Fig. 3), the rebuilt battery assembly 21 and the rebuilt battery cell 31 are manufactured in accordance with steps S5 to S8 for the battery 12 in period B, The vehicle 41 was mounted.

On the other hand, in the third embodiment, after the cells 12 in the period B are selected in the steps S4 and S5, the cells 12 are further layered by the cell resistance BRD. Thereafter, the rebuilt battery assembly 221 and the rebuilt battery 231 are manufactured, and the vehicle 241 is mounted.

Therefore, the following description focuses on the parts different from those of the first embodiment, while the description of the same parts as those of the first embodiment is omitted or simplified.

In the third embodiment as well, the battery 1 as in the first embodiment is rebuilt. That is, similar to the first embodiment, the appearance of the battery 1 is inspected at step S1, and the battery 10 having a problem is removed. Further, the battery resistance BRD is measured (step S2), and the battery 10 in which the abnormal value is detected is removed in step S3.

Subsequently, in step S4, the measured battery resistance BRD is compared with the period threshold Rp. If the battery resistance BRD is smaller than the period threshold value Rp (NO), the process proceeds to step S5, and the battery 11 is determined to be the battery 12 in the B period.

Thereafter, in contrast to the first embodiment, the process proceeds to step S31, where the cells 12 in the period B are divided into the cell resistances BRD in the order of the layer (for example, the cell resistances BRD) (12A, 12B, and 12C). In the battery 12 in the period B, the range of the resistance variation DR of the battery 12 in the use time X is indicated by both arrows in Fig. The cells 12 in the period B have a deviation DR with respect to the cell resistance BRD so that each cell 12 is divided into a plurality of layers (three layers in this example) The batteries 12A and the like having the same battery resistance BRD can be classified.

Subsequently, in step S32, the batteries (for example, the batteries 12A) belonging to one layer among the three layers are collected to form a rebuilt battery aggregate 221 (221A, 221B, 221C) 1 (d)). This makes it possible to prevent a problem such as overvoltage and overcharging of a part of the battery due to the resistance variation DR between the batteries because the variation in characteristics between the batteries used in the battery assembly is further reduced. In addition, since the cells of the period B are used, it is possible to make the rebuilt battery aggregate 221 having stable characteristics with little change in characteristics of each cell even when it is used.

When the number of cells that can be combined is insufficient for one layer, the cells of the adjacent layers, for example, the battery 12A and the battery 12B, or the battery 12B and the battery 12C, A rebuilt battery assembly may be constructed.

Thereafter, the process proceeds to step S7 to form a rebuilt battery cell 231 similarly to the first embodiment by using this rebuilt battery assembly 221 (see FIG. 1 (e)).

This assembled battery 231 has a small variation in characteristics among the batteries used therein and can prevent overvoltage and overcharging of some batteries (or the rebuilt battery aggregate 221) due to the resistance deviation DR between the batteries The problem can be prevented.

In step S8, the rebuilding battery 231 is incorporated in the vehicle 241 (see Fig. 1 (f)), similarly to the first embodiment. Thus, the vehicle 241 carrying the rebuilt battery 231 (the rebuilt battery assembly 221) can be manufactured. Since the vehicle 241 is the same as the vehicle 41 except for the battery module 231, the description thereof is omitted.

Since the vehicle 241 is equipped with the rebuilding battery 231 (rebuilt battery pack), the vehicle 241 can be made inexpensive as compared with the case of using a new battery (assembled battery) Effective utilization can be planned.

In the third embodiment, step S2 corresponds to the resistance measurement step, step S4 corresponds to the resistance discrimination step, step S31 corresponds to the resistance layer step, and steps S32 and S7 correspond to the second type reconfiguration step.

(Fourth Embodiment)

Subsequently, a fourth embodiment will be described with reference to Figs. 1, 2, and 7 to 9. Fig. In the above-described first embodiment (see Fig. 3), the rebuilt battery assembly 21 and the rebuilt battery cell 31 are manufactured in accordance with steps S5 to S8 for the battery 12 in period B, The vehicle 41 was mounted.

In the third embodiment, after the cells 12 in the period B are selected in the steps S4 and S5, the cell 12 is again layered with the cell resistance BRD. Thereafter, the rebuilt battery assembly 221 and the rebuilt battery 231 were manufactured, and the vehicle 241 was mounted.

On the other hand, in the fourth embodiment, similarly to the third embodiment, the cells 12 in the period B are selected in steps S4 and S5, and then layered on the cells 12 again. However, in the third embodiment, the size of the battery resistance BRD is divided into layers, but the layer is divided into the discharge time DT of the battery.

Therefore, the following description focuses on the parts different from those of the first and third embodiments, while the description of the same parts as those of the first and third embodiments is omitted or simplified.

First, the relationship between the battery temperature BT and the battery resistance BRD (temperature characteristic of the battery resistance BRD) in the battery 1 (12) will be described with reference to Fig. As can be seen from this graph in Fig. 7, the battery 1, which is a Ni-MH battery for in-vehicle use, can be used in the usable temperature range UTR (-30 to 60 DEG C in the battery 1).

Temperature range (hereinafter referred to as " high-temperature region H ") of the range from a low temperature (20 deg. C) to about 60 deg. BRD) (internal resistance of the battery) becomes low. This is because, in the battery 1, the battery reaction sufficiently occurs. In this temperature range, even when the battery temperature BT changes, the variation of the battery resistance BRD is small, but the battery resistance BTD tends to decrease linearly as the battery temperature BT increases.

On the other hand, when the battery temperature BT is in a temperature range of -20 占 폚 or below (low temperature region L described later), for example, -30 占 폚, the battery resistance BRD increases in the high temperature region H (In this example, five times or more) of the battery resistance BRD in the case where the battery is used. And the battery resistance BRD rapidly increases as the battery temperature BT decreases.

In the temperature range of 10 占 폚 to -20 占 폚 (intermediate temperature region M described later) between them, the battery resistance BRD increases as the battery temperature BT decreases.

Therefore, as shown in Fig. 7, the temperature region of 10 to 60 占 폚, at which the battery resistance BRD linearly decreases as the temperature rises, is set to the high temperature region H in this battery 1 . A temperature region of -20 占 폚 or lower (-30 to -20 占 폚) is defined as a low-temperature region (L). The temperature range between -20 and + 10 占 폚 between them is referred to as an intermediate temperature region (M).

Further, at -30 캜 or lower, the resistance of the electrolyte of the battery 1 becomes high, making it difficult to use. On the other hand, if it exceeds 60 ° C, charging becomes difficult and the use becomes difficult.

The battery 1 (12) is set to a full charge state (SOC 100%: battery voltage (BV) = maximum allowable voltage (Vmax)) and discharged at a maximum electric power of 10 C through the charge / The time variation of the battery voltage BV until the terminal voltage (battery voltage BV) of the battery becomes the allowable minimum voltage Vmin (SOC 0%) becomes as shown in Fig. 8, the relationship between the discharge time DT and the battery voltage BV largely depends on the battery temperature BT. As the battery temperature BT is lower, the battery voltage BV is lowered The battery voltage BV decreases in a short period of time.

8, even when the battery 12 (indicated by the symbols S and T) in the same B period is used, the solid line (battery T) is formed by the resistance deviation DR of the battery, There may be a difference in the relationship between the discharge time DT and the battery voltage BV as indicated by broken lines (battery S). (-25),? (0),? (-10), and? (-10) are compared with the discharge time DT from the start of discharge to the allowable minimum voltage Vmin, It can be seen that the discharge time difference DELTA indicated by DELTA (-30) has temperature dependency. Specifically, in the high temperature region H (10 to 50 DEG C), the discharge time difference DELTA is relatively small as indicated by DELTA (25). Similarly, even in the low temperature region L (-30 to -20 占 폚), the discharge time difference? Is relatively small as indicated by? (-30). It can be seen that the discharge time difference DELTA is relatively large as indicated by DELTA (O) and DELTA (-10) in the intermediate temperature region (-20 to +10 DEG C).

The reason why temperature dependency occurs in the discharge time difference DELTA is considered to be as follows.

That is, since the absolute value of the battery resistance BRD is small in the high temperature region H, even if the battery deteriorates, the variation in resistance is hard to appear as a voltage difference. In addition, in the low temperature region L, the resistance of the electrolyte solution in the battery resistance BRD is dominant, and the contribution of the electrode resistance becomes small, so that a significant difference in battery deterioration can not be found. On the other hand, it is considered that the resistance of the electrode in the battery resistance BRD is dominant in the intermediate temperature region M, and the deviation of electrode characteristic deterioration easily occurs.

It is therefore possible to distinguish the battery resistance BRD measured by the DC-IR method by discharging the battery 1 while keeping the battery temperature BT at a specific temperature in the intermediate temperature region M It can be seen that the difference in the characteristics of the cells without being detected can be detected.

In Fig. 8, the battery voltage BV from the full charge state (SOC 100%: the maximum allowable voltage Vmax) to the discharge end voltage Ved (SOC 0%; Allowed minimum voltage (Vmin)].

However, as the discharge starting voltage Vst for starting the discharge, the allowable voltage range (Vmin to Vmax) from the allowable minimum voltage (Vmin) to the allowable maximum voltage (Vmax) is divided into five A value within the high voltage range of the upper-side 1/5 can be selected. This is because discharging is started from a value close to the allowable maximum voltage Vmax (voltage of full charge (SOC: 100%)), so that the characteristic of the battery with a relatively large charged amount can be reflected in the discharging time DT . Therefore, the discharge start voltage Vst is preferably a voltage value of the allowable maximum voltage Vmax (full charge (SOC: 100%)).

As the discharge end voltage Ved that terminates the discharge, when a value within the lower one-fifth low voltage range corresponding to the uppermost one of the five ranges in which the allowable voltage range (Vmin to Vmax) is divided into five is selected do. It is possible to reflect the battery characteristic in a state of a relatively low charge amount to the discharge time DT by discharging to a value close to the allowable minimum voltage Vmin (voltage of the full discharge (SOC: 0%)]. Therefore, as the discharge end voltage Ved, the voltage value of the allowable minimum voltage Vmin (full discharge (SOC: 0%)) is preferable.

In the present embodiment, the current to flow at the time of discharging is 10 C or less. When a large current is caused to flow, the discharging is terminated in a short time, so that the measurement accuracy of the discharging time DT is lowered and it becomes difficult to appropriately compare the discharging time difference DELTA. This is because the influence of the voltage drop due to the resistance of the electrolyte generated to discharge a large current is large and it becomes difficult to grasp the change in the discharge time DT caused by the deterioration of the characteristics of the battery electrode.

Also in the fourth embodiment, the battery 1 as in the first and third embodiments is rebuilt. That is, the appearance of the battery 1 is inspected in step S1 of Fig. 9, and the battery 10 having a problem is removed. Further, the battery resistance BRD is measured (step S2), and the battery 10 in which the abnormal value is detected is removed in step S3.

Subsequently, in step S4, the measured battery resistance BRD is compared with the period threshold Rp. If the battery resistance BRD is smaller than the period threshold value Rp (NO), the process proceeds to step S5 where the battery 11 is determined to be the battery 12 of period B.

Thereafter, in place of the step S31 in the third embodiment (in the fourth embodiment, the step S31 shown by the broken line in FIG. 9 is not performed), the battery 12 in the period B is replaced with the discharge Time (DT). Specifically, the battery voltage (BV) was previously set at 1.7 V / cell (discharge start voltage (Vst)) which is the full charge voltage and the battery temperature The discharge time DT until the cell voltage BV reaches the discharge end voltage Ved of 0.9 V / cell is measured and a plurality of layers (for example, the discharge time DT (Three layers of the batteries 12P, 12Q and 12R) in the shortest order].

By this layer, it is possible to suitably detect the difference in cell characteristics under an environment of an intermediate temperature region (M) at a comparatively low temperature, which is unknown in the cell resistance (BRD) under normal temperature, and each cell can be divided into a plurality of layers. Thus, the used secondary batteries having similar characteristics can be accurately collected. Particularly, in the use of the battery under an environment of the intermediate temperature region M in which the battery resistance BRD is slightly increased at a relatively low temperature, those having the same characteristics can be selected, It is possible to easily form a battery assembly (a small battery pack) having a stable characteristic and a combined battery (a large battery pack) combined with the battery assembly in a practical use of the battery 1 with little difference in battery characteristics.

Therefore, the process advances to step S42 to collect the cells (for example, the batteries 12P) belonging to one layer among the plurality of layers (in this example, three layers in this example) to form a rebuilt battery aggregate 321 (321P, 321Q and 321R) (see Fig. 1 (d)). This makes it possible to prevent problems such as overvoltage and overcharging of some of the batteries due to characteristic deviations between batteries, which are particularly small in the characteristics deviation between cells used in the battery aggregate. In addition, since the cells of period B are used, the characteristics of each cell are less changed even when they are used, and the rebuilt battery assembly 321 having stable characteristics can be obtained.

Particularly, in the use in an environment of the intermediate temperature region M, since the cells 12P having the same characteristics are used in combination, in actual use of the battery under the environment of the intermediate temperature region M, So that the cell aggregate 321 having a stable characteristic can be obtained.

When the number of cells that can be combined is insufficient for one layer, the cells of the adjacent layers, for example, the battery 12P and the battery 12Q, or the battery 12Q and the battery 12R, The rebounded battery assembly 321 may be constructed.

Thereafter, the process advances to step S7 to form a rebuilt battery cell 331 as in the first and third embodiments by using the rebuilt battery assembly 321 (see FIG. 1 (e)), .

This assembled battery 331 has a particularly small variation in characteristics among the batteries used therein, and causes problems such as overvoltage and overcharging of some batteries (or the rebuilt battery assemblies 321) Can be prevented. Particularly, in the practical use of the battery in an environment of the intermediate temperature region M, it is possible to make the battery module 331 stable in characteristics with less difference in battery characteristics.

In step S8, a rebuilding battery 331 is built in the vehicle 341 as in the first and third embodiments (see Fig. 1 (f)). Thus, it is possible to manufacture the vehicle 341 carrying the rebuilt battery 331 (the rebuilt battery assembly 321). The vehicle 341 is the same as the vehicle 41 except for the battery module 331, and a description thereof will be omitted.

Since the vehicle 341 also includes the rebuilding battery 331 (rebuilt battery pack), it can be made inexpensive as compared with the case of using a new battery (assembled battery) Can be effectively utilized.

In the fourth embodiment described above, the step S31 shown by the broken line in FIG. 9 is omitted, and the battery 12 in the period B in the step S41 is layered by the discharge time DT.

However, step S31 shown by the broken line in Fig. 9 may be omitted, and step S31 and step S41 may be performed for two layers. That is, the cells 12 in the period B may be first layered by the cell resistance BRD in step S31, and each layered cell may be layered again in the discharge time DT in step 41. [

In the fourth embodiment, step S2 corresponds to the resistance measuring step, step S4 corresponds to the resistance discrimination step, step S41 corresponds to the discharge time layer step, and steps S42 and S7 correspond to the third type reconfiguration step or the fourth type reconfiguration step .

(Fifth Embodiment)

Next, a fifth embodiment will be described. The hammer drill 60 of the fifth embodiment is a battery-powered device in which a rebuilt battery assembly 61 in which the batteries 12 of the first embodiment are assembled and reconfigured is mounted. 10, the hammer drill 60 accommodates a rebuilt battery assembly 61 on the bottom portion 63 of the main body 62, and uses the rebuilt battery assembly 61 as an energy source for driving the drill have.

Since the hammer drill 60 includes the above-described rebuilt battery assembly 61, it can be made inexpensive as compared with the case of using a battery assembly using a new battery, and the battery can be effectively used .

While the present invention has been described based on the first to fifth embodiments, the present invention is not limited to the first to fifth embodiments described above, but may be modified as appropriate without departing from the gist of the present invention Of course, it can be applied.

For example, in the above-described first to fifth embodiments, a nickel-hydrogen secondary battery is exemplified as the battery 1. However, the present invention can be applied to other types of secondary batteries such as lithium ion secondary batteries and nickel-cadmium batteries.

In the first to fifth embodiments, the battery of the prismatic battery is exemplified, but the present invention can also be applied to a cylindrical battery or the like. Further, although a battery having a stacked type power generation element is exemplified, the present invention can also be applied to a battery having a winding type power generation element. Further, although the direct current resistance of the battery measured by the DC-IR method is used as the battery resistance, alternating current resistance of the battery using the AC-IR method may be used.

1: Battery (used secondary battery)
11, 12, 13, 14, 15: Selected (layered) cells
21, 121, 221, 221A, 221B, 221C, 321, 321P, 321Q, 321R: Rebuilt battery assembly (rebuilt battery pack)
31, 131, 231, 331: Rebuilt battery (Rebuilt battery pack)
41, 141, 241, 341: vehicle
42: engine
43: Front motor
44: rear motor
45: Body
46: Cable
47: Inverter
60: Hammer drill (battery-operated machine)
61: Battery pack
62: Body of hammer drill
63: bottom (of main body)
UBP: used cell aggregate
UAB: Used battery
UP: Availability period
A: A period (initial resistance period: initial stage)
B: Period B (Medium-term resistance period: Medium-term stage)
C: C period (endurance high period: boil phase)
UT: Operating time (of battery)
BRD: Battery resistance
Rmin: Permissible minimum resistance value (of battery resistance)
Rmax: Permissible maximum resistance value (of battery resistance)
Rp: duration threshold (of battery resistance)
Ri: initial resistance
DR: resistance variation
BT: battery temperature
UTR: Available temperature range (of battery)
H: high temperature region
M: medium temperature region
L: low temperature region
Vst: Discharge start voltage
Ved: Discharge end voltage
Vmax: Allowable maximum voltage
Vmin: allowable minimum voltage
BV: Battery voltage
DT: Discharge time
DELTA: Discharge time difference
S, T: Battery in period B
S2: Resistance measurement step
S4: Resistance discrimination step
S12: Period determining step
S31: Step for each resistive layer
S41: Step for discharge time layer
S6, S7: First Type Reconstruction Step
S32, S7: second type reconstruction step
S42, S7: a third type reconstruction step, a fourth type reconstruction step

Claims (18)

The battery resistance gradually decreases in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears,
The medium-resistance low period in which the battery resistance is relatively low appears in the middle stage of the usable period,
A secondary battery selecting method for a secondary battery which is used for a secondary battery having a characteristic in which the battery resistance gradually increases at an end stage of the usable period and at the same time,
A resistance measuring step of measuring a battery resistance of the used secondary battery,
It is determined whether the battery resistance of the used secondary battery is larger or smaller than the period threshold for identifying whether the used secondary battery is in the initial resistance high period or the remainder resistance high period and the middle resistance period And a step of discriminating the used secondary battery. The secondary battery according to claim 1, wherein, for the used secondary battery having the battery resistance larger than the period threshold, based on usage history information of the used secondary battery, the used secondary battery belongs to the initial resistance high period And a period discriminating step of discriminating whether or not the rechargeable battery belongs to the rechargeable battery and whether or not the rechargeable battery belongs to the rechargeable battery. The method according to claim 1, further comprising the step of dividing the used secondary battery having the battery resistance smaller than the period threshold into a plurality of layers according to the size of the battery resistance. 3. The method according to claim 2, further comprising the step of dividing the used secondary battery having the battery resistance smaller than the period threshold into a plurality of layers according to the size of the battery resistance. 5. The secondary battery according to any one of claims 1 to 4,
Within the usable temperature range,
The DC resistance of the battery increases as the temperature of the battery decreases,
The change of the direct current resistance due to the temperature is small in the high temperature region of relatively high temperature,
The DC resistance is greatly changed by the temperature in the low temperature region of relatively low temperature and the DC resistance is three times or more of the DC resistance in the high temperature region,
In the intermediate temperature region between the high temperature region and the low temperature region, there is a characteristic in which the DC resistance accelerates as the temperature of the battery decreases,
The secondary battery having the battery resistance smaller than the period threshold or layered at the step of each resistor layer,
Under the environment of the intermediate temperature region,
And a constant discharge discharge or a constant-current discharge is performed from a predetermined discharge start voltage within a high voltage range of 1/5 of the upper half of the allowable voltage range from the allowable minimum voltage to the allowable maximum voltage, Based on the length of the discharge time up to the discharge end voltage,
And a discharge time layer layer step of layering again into a plurality of layers. The battery resistance gradually decreases in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears,
The medium-resistance low period in which the battery resistance is relatively low appears in the middle stage of the usable period,
A rechargeable battery pack having a characteristic in which a battery resistance gradually increases at an end stage of a usable period and a rechargeable battery having a relatively high resistance period exhibits a relatively high resistance and a plurality of used secondary batteries already used are reconfigured ,
Wherein the secondary battery is in the middle-period low resistance period by the secondary battery sorting method according to claim 1. The battery resistance gradually decreases in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears,
The medium-resistance low period in which the battery resistance is relatively low appears in the middle stage of the usable period,
A rechargeable battery pack having a characteristic in which a battery resistance gradually increases at an end stage of a usable period and a rechargeable battery having a relatively high resistance period exhibits a relatively high resistance and a plurality of used secondary batteries already used are reconfigured ,
Wherein the used secondary battery is all in the initial resistance high period by the secondary battery selection method according to claim 2. The battery resistance gradually decreases in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears,
The medium-resistance low period in which the battery resistance is relatively low appears in the middle stage of the usable period,
A rechargeable battery pack having a characteristic in which a battery resistance gradually increases at an end stage of a usable period and a rechargeable battery having a relatively high resistance period exhibits a relatively high resistance and a plurality of used secondary batteries already used are reconfigured ,
The secondary battery according to claim 3, wherein the used secondary battery belongs to one layer or a part of adjacent layers among a plurality of layers layered by the step of the resistive layer, Battery pack. The battery resistance gradually decreases in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears,
The medium-resistance low period in which the battery resistance is relatively low appears in the middle stage of the usable period,
A rechargeable battery pack having a characteristic in which a battery resistance gradually increases at an end stage of a usable period and a rechargeable battery having a relatively high resistance period exhibits a relatively high resistance and a plurality of used secondary batteries already used are reconfigured ,
The secondary battery according to claim 4, wherein the used secondary battery belongs to one layer of a plurality of layers separated by the step of the resistance layer or a part of adjacent layers, Battery pack. The battery resistance gradually decreases in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears,
The medium-resistance low period in which the battery resistance is relatively low appears in the middle stage of the usable period,
A rechargeable battery pack having a characteristic in which a battery resistance gradually increases at an end stage of a usable period and a rechargeable battery having a relatively high resistance period exhibits a relatively high resistance and a plurality of used secondary batteries already used are reconfigured ,
The secondary battery according to claim 5, wherein the used secondary battery belongs to one layer or a part of adjacent layers among the plurality of layers layered by the discharge time layer layer step Built-in battery pack. The battery resistance gradually decreases in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears,
The medium-resistance low period in which the battery resistance is relatively low appears in the middle stage of the usable period,
A rechargeable battery pack having a characteristic in which a battery resistance gradually increases at an end stage of a usable period and a rechargeable battery having a relatively high resistance period exhibits a relatively high resistance and a plurality of used secondary batteries already used are reconfigured ,
Wherein said secondary battery belongs to said middle-period low resistance period. 11. A vehicle in which the rebuilt battery pack according to any one of claims 6 to 9 and 11 is mounted and electric energy from the rebuilt battery pack is used for all or a part of the power source. 11. A vehicle in which the rebuilt battery pack according to claim 10 is mounted and electric energy from the rebuilt battery pack is used for all or a part of the power source. 11. A battery-operated device comprising the rebuilt battery pack according to any one of claims 6 to 9 and using the rebuilt battery pack as at least one of energy sources. 11. A battery-operated device comprising the rebuilt battery pack according to claim 10, wherein the rebuilt battery pack is used as at least one of the energy sources. The battery resistance gradually decreases in the initial stage of the usable period, the initial resistance high period in which the battery resistance is relatively high appears,
The medium-resistance low period in which the battery resistance is relatively low appears in the middle stage of the usable period,
A rechargeable battery pack having a characteristic in which the battery resistance gradually increases at the end of the usable period and the rechargeable battery has a characteristic in which the battery resistance is relatively high, And
It is determined whether the battery resistance of the used secondary battery is larger or smaller than the period threshold for identifying whether the used secondary battery is in the initial resistance high period or the remainder resistance high period and the middle resistance period A resistance determination step of determining,
And a first type recomposing step of collecting the used secondary batteries having the battery resistance smaller than the period threshold value and reconstructing the battery pack. The method according to claim 16, further comprising the step of dividing the used secondary battery into a plurality of layers according to the size of the battery resistance, with respect to the used secondary battery having the battery resistance smaller than the period threshold value,
And a second type reconstruction step of reconstructing the battery pack by collecting used secondary batteries belonging to one layer or a part of adjacent layers of the plural layers separated by the battery resistance instead of the first type reconstruction step (Method for manufacturing a built - in battery pack). 18. The secondary battery according to claim 16 or 17,
Within the usable temperature range,
The DC resistance of the battery increases as the temperature of the battery decreases,
The change of the direct current resistance due to the temperature is small in the high temperature region of relatively high temperature,
Temperature range of a relatively low temperature and a direct current resistance of three times or more the DC resistance in a high temperature region,
In the intermediate temperature region between the high temperature region and the low temperature region, there is a characteristic in which the DC resistance accelerates as the temperature of the battery decreases,
The secondary battery having the battery resistance smaller than the period threshold or layered at the step of each resistor layer,
Under the environment of the intermediate temperature region,
And a constant discharge discharge or a constant-current discharge is performed from a predetermined discharge start voltage within a high voltage range of 1/5 of the upper half of the allowable voltage range from the allowable minimum voltage to the allowable maximum voltage, Based on the length of the discharge time up to the discharge end voltage,
And a step of a discharge time layer layer which is divided into plural layers again,
A second type recomposing step or a second type recomposing step in which a secondary battery belonging to one layer or a part of adjacent layers among a plurality of layers laminated by the length of the discharge time is collected to reconstitute a battery pack 3 type recomposing step.

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